CN104988931A - Single supporting leg and clamping plate type flexible device for constructing temporary supports - Google Patents

Abstract

The utility model relates to a single-leg splint-type active device for temporary roof support, which includes a splint, a fixed leg, a movable leg, and high-strength bolts. Among them, the outer surface of the leg and the inner wall of the splint are processed with grooves that can engage with each other, and a bolt fixing block is set on the splint for clamping the nut, which is convenient for fastening operations. One end of the solid round steel is welded with an end plate at the leg. Use two splints to clamp the two outriggers through high-strength bolts. The grooves on the inner wall of the splint and the grooves of the outriggers engage with each other. When the high-strength bolts are tightened during loading, the arc-shaped inner wall of the splint squeezes and occludes the outriggers to form a single Outrigger splint type active device. The two ends of the single-leg splint type flexible device, that is, the end plate at the fixed leg and the end plate at the movable leg, are respectively connected to the steel support pipe. The single-leg splint-type activating device has large telescopic length, high rigidity, high bearing capacity, can be reused, has wide application fields, and has remarkable comprehensive benefits.

Description

A single-leg splint-type flexible device for temporary roof support in construction

technical field

The invention relates to a single-leg splint-type activating device for temporary roof support, which is used for applying pre-loaded axial force to steel supports, and belongs to the technical field of infrastructure construction auxiliary workpieces. It can be applied to support in foundation pit, temporary support of bridge, steel support of underground excavation tunnel, etc.

Background technique

In large-scale infrastructure construction projects such as foundation pit engineering, underpass bridge construction, and underground excavation tunnels, steel supports as support structures play a very important role in maintaining the stability of the excavation surface and limiting the displacement of the bridge body. At present, the active devices supported by steel adopt wedge-shaped active devices and box-type active devices. In both methods, after the prestress is applied with the jack, the steel wedge is driven in, and the jack is withdrawn after being stabilized. The force is transmitted by the steel wedge, which is likely to cause stress concentration at the steel wedge, and the stiffness of the connection node of the active device is small, and the local area is easy to buckle. During the excavation process of foundation pits and buried tunnels, as the depth increases, the earth pressure acting on the supporting structure increases, which requires steel supports with greater rigidity and bearing capacity to maintain foundation pits or buried tunnels. The stability of the tunnel excavation surface; at the same time, the fixed section of the steel support has definite specification parameters, which requires a steel support active device with a certain amount of adjustable expansion and contraction to adjust the length of the steel support to adapt to the excavation of the foundation pit and Dig tunnels of different widths. When the construction of the bridge under the underground project causes uneven subsidence of the bridge pier, it will have an adverse effect on the force of the bridge. Therefore, during the construction of the underpass of the underground project, it is necessary to temporarily support the beam structure and adjust it after the completion of the underground project. Or replace the bridge support. At present, hydraulic jacks are mostly used for bridge support construction, but the hydraulic pressure of hydraulic jacks is not easy to maintain for a long time. With the increasing number of foundation pit projects, underpass bridge construction, and underground excavation tunnel projects in my country, it is urgent to solve the problem of poor integrity of the steel support system. Therefore, the steel support active device needs to study and adopt a new structure to strengthen the rigidity of the steel support and ensure the bearing capacity. Capable and reliable.

Contents of the invention

Based on the above requirements, the present invention proposes a single-leg splint-type flexible device for temporary roof support. The two splints are connected by high-strength bolts. The arc-shaped inner wall of the splint and the outer surface of the leg are punched and planed into grooves that can engage with each other. The arc-shaped contact surface of the inner wall of the two splints squeezes the leg to generate friction. and the occlusal force to bear and transmit the axial force of the steel support. Finally, the two splints and the outrigger are compressed by tightening the high-strength bolts, and the two are stably fixed together. The splint of the single-leg splint type active device is in contact with the arc surface, and the integrity is good; the device is assembled and disassembled by tightening and loosening high-strength bolts, and the operability is strong; the splint type active device can effectively bear the steel support The axial pressure can also withstand the tensile force of the outward deformation of the soil layer, and the integrity of the purlin and steel support has been improved.

For reaching above-mentioned requirement, technical scheme of the present invention is as follows:

A single-leg splint-type active device for temporary roof support, the device includes a splint 1, a fixed leg 2, a movable leg 3, and high-strength bolts 4; two splints 1 are arranged in parallel, and the cut splint 1 Bolt holes 5 are arranged symmetrically at the ends, and one end of the bolt holes 5 is provided with a nut fixing block 11, and the inner wall of the splint 1 is punched and planed into a groove 10; One end of the round steel I6 is welded with the end plate 7 at the fixed leg, and the outer surface of the solid round steel I6 is punched and planed to form a groove 10 interlocking with the inner wall of the plywood 1; the movable leg 3 includes the solid round steel II8 and the end plate at the movable leg 9. One end of the solid round steel Ⅱ8 is welded with an end plate 9 at the outrigger. The outer surface of the solid round steel Ⅱ8 is punched and planed to form a groove 10 interlocking with the inner wall of the plywood 1; the high-strength bolt 4 is made by cutting an ordinary high-strength bolt. The circular section nut of ordinary high-strength bolt is cut along a straight line, and the cutting straight line is tangent to the outer wall of the screw rod of high-strength bolt 4, and the nut through cutting is stuck on the nut fixing block 11, which is convenient for fastening operation. The two splints 1 clamp the fixed outrigger 2 and the movable outrigger 3 through high-strength bolts 4. The inner wall of the groove of the splint 1 is in contact with the friction surface of the outrigger groove. When loading, the high-strength bolts 4 are tightened so that the circular The curved inner wall presses and occludes the surfaces of the supporting legs to form a single-leg splint type active device 12 .

The two ends of the single-leg splint type movable device 12, namely, the end plate 7 at the fixed leg and the end plate 9 at the movable leg are respectively connected with the steel support pipe 14. The solid round steel I6 has the same center as the end plate 7 at the fixed leg, the solid round steel II8 has the same center as the end plate 9 at the movable leg, and the solid round steel I6 has the same center as the solid round steel II8.

Further, the total length of the fixed leg 2 and the movable leg 3 is 300-500 mm, and the length of the splint 1 is 300-500 mm. The thickness of the end plate 7 at the leg is 20-30mm, which is used to prevent the large deformation of the end plate at the top of the leg due to the excessive axial force of the steel support.

Furthermore, the upper half of the plywood 1 is processed by welding thick steel plates on both sides after cutting thick-walled steel pipes. One side of the steel plate is cut to match the outer edge of the thick-walled steel pipe. Bolt holes are arranged symmetrically in the direction, the height of the bolt holes is 60-80mm, the thickness of the steel pipe is 55-65mm, and the height of the steel plate is 60-65mm. At intervals of 50-60mm, there are flanges welded around thick-walled steel pipes and thick steel plates, the outer right-angle sections of the flanges are chamfered, and the thickness of the flanges is 20mm.

Further, the lower half of the splint 1 is reprocessed on the basis of the half of the splint, and it is close to the outer wall of the thick-walled steel pipe, the thick steel plate plus the welding nut fixing block 11, and there is a welded joint between each two wing plates. The length of the nut fixing block 11 is the distance between two wing plates, the length straight line of the nut fixing block 11 is circumscribed with the bolt hole, and the height is 10-15mm.

Further, the bolt holes on the splint 1 are arranged in two rows along the length direction, and the total number of bolt holes is 8-12. The distance between the centers of the bolt holes of the upper half set and the lower half set of the splint 1 is 60-90 mm, and the distance between the center of the bolt holes and the edge of the splint is 20-50 mm.

Further, the high-strength bolts used have a diameter of 20-30mm, and the circular cross-section nuts of the high-strength bolts are cut once, and the cutting line is tangent to the outer wall of the screw.

Further, the circular arc surfaces of the upper and lower half sets of the splint 1 and the outer walls of the legs are planed into grooves that can engage with each other.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention proposes a single-leg splint-type activating device for temporary roof construction. The two splints engage the legs through tightening and extrusion of high-strength bolts. The splint and the legs are in contact with the arc surface, and the structure is The integrity is better, reducing the risk of steel support falling off;

2. The present invention proposes a single-leg splint-type active device for temporary roof support. This device is composed of splints, legs and high-strength bolts. It has few component types, small dead weight, low cost, flexible use, and economical Significant benefits;

3. The present invention proposes a single-leg splint-type movable device for temporary roof support, which can be assembled and disassembled by tightening and loosening bolts, which is convenient and quick. The device has large retractable length, high rigidity, sufficient bearing capacity, can be reused, has remarkable comprehensive benefits, and has important engineering application value and development prospect.

Description of drawings

Fig. 1 is the schematic front view of the single-leg splint type activating device of the present invention;

Fig. 2 is a schematic top view of a single-leg splint type active device of the present invention;

Fig. 3 is a schematic diagram of the pre-applied axial force applied by the jack of the present invention;

Fig. 4 is a left view schematic diagram of a cross-section of a single-leg splint type active device of the present invention (at the high-strength bolt);

Fig. 5 is a schematic diagram of a cross-sectional right view of a single-leg splint type active device of the present invention (at the high-strength bolt);

Fig. 6 is the schematic front view of splint of the present invention;

Fig. 7 is the cross-sectional schematic view (bolt hole place) of splint of the present invention;

Fig. 8 is a schematic top view of a splint of the present invention;

Fig. 9 is a schematic front view of a bolt of the present invention;

Fig. 10 is a schematic top view of the bolt of the present invention;

Fig. 11 is a schematic view of the front (top) view of the legs of the present invention;

Fig. 12 is a schematic left view of the fixed leg of the present invention;

Fig. 13 is a schematic view of the right side of the movable outrigger of the present invention;

Fig. 14 is a schematic front view of the present invention for a bridge support system

Fig. 15 is a schematic sectional view of the present invention for a bridge support system;

In the figure, 1- splint, 2- fixed leg, 3- movable leg, 4- high-strength bolt, 5- bolt hole, 6- solid round steel Ⅰ, 7- end plate at fixed leg, 8- solid round steel Ⅱ, 9-end plate at the movable leg, 10-groove, 11-nut fixing block, 12-single leg splint type active device, 13-steel support standard section, 14-steel support pipe, 15-bridge span , 16-Abutment, 17-Support, 18-Pier, 19-Jack

Detailed ways

A single-leg splint type active device for temporary roof support, characterized in that there are four different types of components, including splint 1, fixed leg 2, movable leg 3, and high-strength bolts 4; The splint 1 includes two splints, which are arranged in parallel, and the two ends of the cut splint 1 are symmetrically provided with bolt holes 16, and one end of the bolt hole is provided with a nut fixing block 11, and the inner wall of the splint is planed into a groove 10 for engagement; 2 includes solid round steel I6, end plate 7 at the fixed outrigger, one end of solid round steel I6 is welded with end plate 7 at the fixed outrigger, the outer surface of solid round steel I6 is punched and planed into grooves 10 that can engage with the inner wall of the plywood, Used to interlock with the grooves on the inner wall of the splint; the movable leg 3 includes solid round steel Ⅱ8, end plate 9 at the movable leg, one end of the solid round steel Ⅱ8 is welded with the end plate 9 at the leg, and the outer surface of the solid round steel Ⅱ8 is punched Plane into a groove 10 that can interlock with the inner wall of the plywood; the high-strength bolt 4 is made by cutting the ordinary high-strength bolt, and the circular cross-section nut of the ordinary high-strength bolt is cut along a straight line, and the cutting line is tangent to the outer wall of the screw rod. The nut is stuck on the nut fixing block 11, which is convenient for fastening operation. The two splints clamp the fixed leg 2 and the movable leg 3 through high-strength bolts 4, and the groove inner wall of the splint 1 and the groove of the movable leg 3 are engaged with each other. The surface of the support leg is extruded and engaged to form a single-leg splint type active device 12 .

The two ends of the single-leg splint-type activating device 12, that is, the end plates 7 at the two fixed legs and the end plates 9 at the three movable legs are respectively connected to the steel support pipe 14. The center of the solid round steel I6 is the same as that of the end plate 7 at the fixed leg, the center of the solid round steel II8 is the same as that of the end plate 9 at the movable leg, and the center of the solid round steel I6 is the same as that of the end plate 9 at the movable leg.

The upper half of the plywood 1 is made of Q235 steel plate with a width of 320mm and a thickness of 160mm. The length is 400mm. Five pairs of bolt holes are arranged symmetrically on both sides.

The lower half of the plywood 1 is made of Q235 steel plate with a width of 320mm and a thickness of 160mm. The length is 400mm. Five pairs of bolt holes 5 are arranged symmetrically on both sides. One end of the bolt hole 5 is provided with a nut fixing block 11, which withstands the nut and prevents the wrench from twisting when the wrench applies force to the nut.

The fixed leg 2 is processed from Q235 solid round steel with a diameter of 200mm and a length of 100mm. The outer surface of the solid round steel is punched and planed into a groove 10 that can engage with the inner wall of the splint, and one end of the solid round steel is welded to the end plate 7 at the leg with a thickness of 20mm.

The movable support leg 3 is processed by Q235 solid round steel with a diameter of 200mm, and the length is 300mm. The outer surface of the solid round steel is punched and planed into a groove 10 interlocking with the inner wall of the plywood. One end of the solid round steel is welded to the end plate 9 at the movable outrigger place with a thickness of 20mm.

The connection between the splint 1 and the fixed leg 2 and the movable leg 3: Use two splints to clamp the two legs through the high-strength bolt 4, the groove on the inner wall of the splint 1 and the groove on the outer surface of the leg are engaged with each other, and pass through when loading The tightening of the high-strength bolts makes the splint extrude and occlude the surface of the support leg to form a single-leg splint type active device 12 .

The invention has a wide range of application fields, and can be applied to supports in foundation pits, bridge construction support roofs, steel supports for underground excavation tunnels, and the like.

With the increase of underground tunnel projects, the surrounding environment faced by underground engineering construction is becoming more and more complex, and there are more and more cases of passing through existing buildings at close range. When the tunnel project passes through the existing bridge pile foundation or is constructed in the adjacent area, due to the disturbance of the stratum due to the tunnel excavation, the change of the stratum stress causes the compression and deformation of the soil, and the interaction between the pile foundation and the soil further causes bridge damage. The settlement and differential settlement of the substructure will cause additional internal force on the superstructure sensitive to deformation, which will affect the safety of the bridge structure. In order to ensure the safety of tunnel construction and the use of adjacent bridges, necessary measures need to be taken. Although there are many cases of successful crossing under the condition of traditional grouting reinforcement measures, due to the particularity, unpredictability, complexity of the stratum, human factors in the construction and some factors in the traditional construction method that cannot meet the requirements of precise construction control etc. may lead to accidents. For example, during the construction of a station on Guangzhou Metro Line 3, the underground diaphragm wall collapsed, causing the stratum to subside in the surrounding area of the station, and damage the bearing capacity of the pile foundations of nearby houses, resulting in landslides. When the M10 line of the Beijing subway crossed a certain municipal bridge, only ordinary grouting reinforcement measures were taken, which caused a large number of over-limit cracks in the bridge structure. When the traditional soil reinforcement measures such as grouting and construction methods still cannot meet the safety and stability requirements of the structure, the method of active pre-support should be used to carry out synchronous steel support for the bridge and combined with structural restoration measures, which can effectively control the bridge. The deformation of the upper structure ensures its long-term normal use.

Now in conjunction with accompanying drawings 14-15, the application of the single-leg splint-type movable device in the construction of the bridge roof is illustrated.

Before the tunnel passes through the bridge, the bridge body is actively pre-supported. According to the size of the bridge body structure, steel support pipes of various lengths 14, single-leg splint-type activating devices 12, and high-strength bolts 4 supporting devices are prepared according to the planned amount. The support device is pre-assembled before installation. Each steel pipe support is composed of several steel support standard sections 13, matching steel support pipe 14 and a flexible end. The axis deviation and deflection of the assembled steel support are within the allowable range . Use a crane to erect the supporting device between the abutment 16, the road surface near the pier 18 and the bridge span 15 structure where the support 17 needs to be replaced, and select a jack with a suitable tonnage to place it on the fixed leg of the single-leg splint type active device 12 Between the end plate 7 and the end plate 9 at the movable outrigger. After each jack 19 is ready, slightly tighten the end plates on both sides, and after the jacks are installed, you can start the jacking test. During the jacking test, the space between the two ends of the board is stretched, and the movable outrigger 3 is stretched out accordingly. It can stop when the main beam has not been officially jacked up. At this time, tighten all the high-strength bolts and park it for several hours to observe that there is no change. Only then can the formal ascent begin. After the jacking test is completed, a comprehensive inspection is made before the formal jacking. After the inspection is correct, each oil pump starts simultaneously with the command signal. The whole lifting process implements dual control of bridge deck elevation and jack oil pressure. When starting to lift, all jacks must be under the unified command of professionals to slowly lift up the end plate at the movable outrigger, that is, slowly lift up the bridge body. Control the deformation of the upper structure of the beam in real time. When the requirements are met, tighten all the high-strength bolts of the single-leg splint type active device 12, and the supporting device forms a temporary support. Once the settlement of the substructure exceeds the limit value, the jack starts to lift, and the movable outrigger 3 is extended accordingly, and all high-strength bolts are tightened to form a temporary support for the bridge to ensure that the superstructure of the bridge returns to normal use. After the deformation of the bridge structure is finally stabilized, the restoration measures for the bridge structure will keep the bridge structure working under the stress state allowed by the code. Including adding pads to the bearings, replacing the bearings, redoing the padding stones of the bearings, etc.

The above is a typical example of the present invention, and the practice of the present invention is not limited thereto.

Claims (7)

1. A single-leg splint-type movable device for temporary roof support, characterized in that: the device includes a splint (1), fixed legs (2), movable legs (3), high-strength bolts (4) Two splints (1) are arranged in parallel, bolt holes (5) are arranged symmetrically at both ends of the splint (1) after cutting, and a nut fixing block (11) is arranged at one end of the bolt hole (5), and the inner wall of the splint (1) Punching and planing into grooves (10); the fixed legs (2) include solid round steel I (6), end plates (7) at the fixed legs, and one end of the solid round steel I (6) is welded with an end plate at the fixed legs (7), the outer surface of the solid round steel I (6) is punched and planed into a groove (10) that engages with the inner wall of the splint (1); the movable outrigger (3) includes the solid round steel II (8), the End plate (9), one end of solid round steel II (8) is welded with leg end plate (9), and the outer surface of solid round steel II (8) is punched and planed into grooves ( 10); the high-strength bolt (4) is made by cutting the ordinary high-strength bolt, and the circular cross-section nut of the ordinary high-strength bolt is cut along a straight line, and the cutting straight line is tangent to the outer wall of the screw rod of the high-strength bolt (4), and the cut nut The cap is stuck on the nut fixing block (11), which is convenient for fastening operation; the two splints (1) are clamped by high-strength bolts (4) to the fixed leg (2), the movable leg (3), and the splint (1) The inner wall of the groove is in contact with the friction surface of the groove of the outrigger, and the arc-shaped inner wall of the two splints (1) is squeezed and occluded with the surface of the supporting leg by tightening the high-strength bolt (4) during loading to form a single-leg splint type active device ( 12); The two ends of the single leg splint type movable device (12), that is, the end plate (7) at the fixed leg and the end plate (9) at the movable leg are respectively connected with the steel support pipe (14); the solid round steel I (6) The same circle center as the end plate (7) at the fixed outrigger, the same circle center as the solid round steel II (8) and the same circle center as the end plate (9) at the movable outrigger, the same circle center as the solid round steel I (6) and the solid round steel II (8) . 2. A single-leg splint type movable device for temporary roof support according to claim 1, characterized in that: the total length of the fixed leg (2) and the movable leg (3) is 300- 500mm, the length of the splint (1) is 300-500mm; the thickness of the end plate (7) at the leg is 20-30mm, which is used to prevent the large deformation of the end plate at the top of the leg due to excessive axial force of the steel support. 3. A single-leg splint type activating device for temporary roof support according to claim 1, characterized in that: the upper half of the splint (1) is processed by welding thick steel plates on both sides after cutting thick-walled steel pipes One side of the steel plate is cut into a radian matching the outer edge of the thick-walled steel pipe, and bolt holes are arranged symmetrically along the length direction on the thick steel plate at both ends. The height of the bolt holes is 60-80mm, and the thickness of the steel pipe is 55-65mm. , the height of the steel plate is 60-65mm; at intervals of 50-60mm, a wing plate is welded around the thick-walled steel pipe and the thick steel plate, the outer right-angle section of the wing plate is chamfered, and the thickness of the wing plate is 20mm. 4. A single-leg splint-type movable device for construction of a temporary roof according to claim 1, characterized in that: the lower half of the splint (1) is reprocessed on the basis of the half of the splint. into, close to the outer wall of the thick-walled steel pipe, the thick steel plate plus the welding nut fixing block (11), the nut fixing block (11) is welded in the middle of every two wing plates, and the length is the distance between the two wing plates, The length straight line of nut fixing block (11) is circumscribed with bolt hole, and height is 10～15mm. 5. A kind of single-leg splint type movable device for temporary roof support according to claim 1, characterized in that: the bolt holes on the splint (1) are arranged in two rows along the length direction, and the total number of bolt holes There are 8 to 12 pieces; the center distance between the bolt holes of the upper half set and the lower half set of the splint 1 is 60-90mm, and the distance between the center of the bolt hole and the edge of the splint is 20-50mm. 6. A single-leg splint type activating device for temporary roof support according to claim 1, characterized in that: the high-strength bolts used have a diameter of 20-30mm, and the circular cross-section nuts of the high-strength bolts are cut once, The cutting line is tangent to the outer wall of the screw. 7. A single-leg splint-type movable device for construction of a temporary roof according to claim 1, characterized in that: the arc surface of the upper and lower half sets of the splint (1) and the outer wall of the legs Punch and plan into grooves that can engage with each other.